Description

Spectro Rapid Tester CA-12

Spectro CA-12 is a battery rapid-tester that reads capacity, CCA, and state-of-charge (SoC) in a non-invasive 15-seconds test using electrochemical impedance spectroscopy (EIS). EIS is not new. Size, high cost, long test times and acquired skills to decipher the codes kept this technology in laboratories.

The leading health indicator of a battery is capacity. Assessing capacity is complex, but Cadex made estimation possible by expanding on EIS and developing multi-model electrochemical impedance spectroscopy, or Spectro™.

Spectro CA-12 scans a battery with a 20-2,000 Hertz signal as if to take a landscape. However, the heart of the system is in the patented algorithm. Spectro™ finishes an otherwise lengthy test compiling 40 million transactions in 15 seconds.

Spectro™ should not to be mistaken with impedance testing that reads internal battery resistance. Batteries have improved and resistance-related failures are isolated. This makes much of impedance testing obsolete.

•     Spectro™ is a further development of EIS; it estimates battery capacity on the fly

•     The short test time is made possible with advanced algorithm, the heart of Spectro™

•      DSP shrinks a system that usually rolls on wheels into an elegant hand-held device

•      There are no comparable products on the market

AUTOMOTIVE : Checks starter batteries at garages. Assists battery warranty programs

SPECTRO CA-12 GA

Spectro CA-12 GA battery rapid-tester reads capacity, CCA, and state-of-charge (SoC) of a starter battery in a non-invasive 15-seconds test usingelectrochemical impedance spectroscopy (EIS). Capacity is the leading health indicator of a battery, and Cadex makes capacity estimation possible by expanding on EIS and adding a patented algorithm that completes an otherwise lengthy test of 40 million transactions in 15 seconds. Spectro™ should not to be mistaken with impedance testing that reads internal battery resistance only. Batteries have improved and resistance-related failures are isolated. The CA-12 GA uses a generic matrix that serves most starter batteries and gives a pass/fail on capacity.

Most testers for starter batteries are impedance-based and only read CCA (Cold Cranking Amp). CCA relates to battery resistance that impacts engine cranking. CCA stays steady with age and the readings do not provide reliable health validation. Capacity, on the other hand, fades gradually and offers dependable end-of-life prediction. The figure below illustrates 20 aging starter batteries. All were functional at time of testing.

Capacity and CCA readings of aging batteries. Batteries 1 to 9 have good CCA and high capacities; batteries 10 to 20 are at the end-of-life with capacity loss. All batteries crank well.

“Is there a connection between CCA and capacity,” many wonder? To find out, Cadex examined 175 aging starter batteries and found a 0.55 correlation. Had the readings been closer to 1, the diamond dots in the figure below would have gravitated towards the red reference line. This is not the case, meaning that CCA cannot be used reliably to estimate capacity or predict the end of battery life. Observing the results closer reveals that very few batteries fail due to low CCA; it is the low capacity that eventually pulls CCA down. Note the high number of batteries straddling the 40% capacity cut-off line; the CCA line has almost none. Capacity, not CCA, governs battery health and predicts end-of-life.

Relationship of CCA and capacity on 175 starter batteries  
The correlation is only 0.55. Passing starter batteries dwell in the green acceptance field bound by the 40% capacity threshold and the 50% CCA limit. Capacity is a more dependable health predictor than CCA.  
Note: Capacity and CCA tested according to SAE J537. CCA/capacity correlation is 0.55.

Setting the capacity threshold to 40% and CCA to 50% opens the acceptance field marked in green. The truth table below summarizes the results of Spectro CA-12 GA.

CORRECT CAPACITY PREDICTIONS

Battery anomaly and matrix quality govern accuracy. The generic matrix produces a correct capacity prediction of 84% for AGM (Absorbent Glass Mat) and 82% for flooded lead acid. CCA accuracy is about 90%.

QUICK AND SIMPLE

The generic matrix of the Spectro CA-12 GA makes testing of mid-range starter batteries a breeze and the pass/fail capacity evaluation works well for the service sector. A pass (above 40%) assure 6–12 month additional service, batteries below this level should be replaced. The CA-12 GA also reads CCA and SoC.

Simply select flooded or AGM from the menu and enter CCA and capacity ratings. The battery should have a charge of 40% or higher. If below the acceptable SoC threshold, the instrument advises to charge and retest. Connecting the probes starts the test automatically.

CAPACITY MEASUREMENT IMPROVES PREDICTION

Service personnel may not be aware of the low accuracies of impedance testers. Faulty batteries often pass as good, only to fail on the road, while too many good batteries are replaced by error, causing undue expenses for customers. An independent test lab examining impedance testers reveals a CCA accuracy of only 60–70% with no capacity measurement. Spectro CA-12 GA, in comparison, offers a CCA accuracy of 90% and a capacity sort accuracy of 80–90%. Capacity estimation improves battery valuation by a factor of two and more. The figure below compares the test results of a competitor (impedance tester) with the CA-12 GA.

CCA measurement  
SAE J537 specifies a 30-second discharge at –18°C (0°F) with a current equal to the rated CCA ampere. To pass, the voltage cannot drop below 7.2 volts. Because of complicity, CCA readings are seldom verified.

SPECTRO CA-12 DC  
Spectro CA-12 DC battery rapid-tester reads the capacity of a deep-cycle battery in a non-invasive 15-seconds test using electrochemical impedance spectroscopy (EIS). Capacity is the leading health indicator of a battery, and Cadex makes capacity estimation possible by expanding on EIS and adding a patented algorithm that completes an otherwise lengthy test of 40 million transactions in 15 seconds. Spectro™ should not to be mistaken with impedance testing that reads internal battery resistance only. Batteries have improved and resistance-related failures are isolated. Check our battery matrices for the selection of battery-specific matrix.  
Spectro CA-12 DC makes capacity measurement by discharge obsolete. Spectro™ opens the door to an entirely new way of battery testing by reading the capacity of each monoblock on the fly. More frequent testing reduces downtime while optimizing the service life of each monoblock.

MEASURE CAPACITY IN 15 SECONDS  
Traditional battery testers measure the capacity of deep-cycle batteries by a discharge. The batteries must be fully charged to get correct reading. This is not the case with Spectro CA-12 DC. A partial charge is fine, but if SoC drops below 40%, the unit advises to charge and retest. The test does not stress the battery as a full discharge would. The instrument uses a battery-specific matrix that provides numeric readings for capacity, SoC, internal resistance and voltage.

EASY TO USE  
Simply set the voltage and Ah on Spectro CA-12 DC and connect the probes to the terminals of each monoblock. The batteries do not need to be fully charged or disconnected from the wiring. The unit is reverse polarity and over-voltage protected. The rubberized housing provides a good grip and avoids breakage if dropped.  
A battery may consist of several monoblocks. The CA-12 DC provides the results in minutes of runtime and capacity in percentage. State-of-charge (SoC) is in % and the open circuit voltage (OCV) in V. A GOOD BATTERY meets the test conditions and the display prompts to connect the next monoblock.

In Cart Mode, the capacity of each monoblock is displayed numerically and graphically. The graphic display allows a quick overview of capacity balance. A well-matched battery provides long runtimes and maximum service life. Weak monoblocks in a string can be spotted and replaced. With the ability to measure capacity on the fly, the strong monoblock can be regrouped for a second life.

WHAT ARE TYPICAL BATTERY PROBLEMS?

Capacity evaluation identifies anomalies before performance degradations are noticeable. The examples below illustrate the capabilities of Spectro CA-12 DC in more detail.

LOW CHARGE  
Low charge makes the battery appear weak. Spectro CA-12 is able to read capacity at partial charge and can distinguish between low charge and low capacity. (This is not possible with the discharge method; the battery must always be fully charged to read capacity.)  

LOW CAPACITY  
Low capacity batteries may perform well but have short runtimes. This is similar to a partial charge. The CA-12 DC reads capacity and SoC as distinct values. Low capacity hints to the end-of-battery-life.  

UNBALANCED SET  
A battery string is only as good as the weakest link. The CA-12 DC identifies low performing monoblocks and allows for a timely replacement. Capacity matching with the Spectro CA-12 DC allows battery regrouping of good monoblock for a second life.  

TYPICAL APPLICATIONS  

CENTRAL DATA CONTROL  
Spectro CA-12 DC can be configured to read barcodes for vehicle identification. The CA-12 sends the test results by Bluetooth to a smartphone and from there to a database. Battery history of each vehicle can easily be tracked and controlled.  

SPECTRO CA-12 SOC  
Spectro CA-12 SoC is a battery rapid-tester that reads battery state-of-charge (SoC) in a non-invasive 15-seconds test using electrochemical impedance spectroscopy (EIS). The impedance integrity of a battery remains stable with load. This enables SoC measurement by complex impedance while a battery is under load or immediately after charge (but not during charge). The batteries must be new or well performing.

Troubleshooting electrical systems during fabrication, as well as transportation and showroom activities drains the vehicle battery. A battery should leave the factory with a state-of-charge of about 90%, but verifying by voltage can be inaccurate. Applying a load distorts the voltage, and neutralizing takes up to 24 hours. Voltage based SoC measurements are inherently inaccurate.  
Spectro CA-12 SoC measures battery state-of-charge by impedance signature. The test takes 15 seconds and can be done with a parasitic load, as well as immediately after charge (but not during charge). Surface charge and voltage agitations have minimal effect on the readings. The CA-12 SoC uses an application-defined matrix and displays the SoC in percentage.

APPLICATIONS OF IMPEDANCE-BASED SOC

CAR MANUFACTURING  
Debugging electrical systems causes the battery to drain. Voltage-based SoC readings are inaccurate unless taken after a rest and at open circuit voltage. Voltage fluctuations by battery agitation do not affect the impedance integrity. Spectro CA-12 SoC delivers accurate SoC with a load and right after a charge. The battery must be new.  

DISTRIBUTION  
Opening a car door awakens the vehicle and induces a current flow. The load agitates the battery and voltage no longer provides a dependable SoC reading. The CA-12 SoC measures SoC by impedance, independent of voltage. (Does not apply while battery is charging.)  

CREATING A MATRIX  
Prepare new batteries to state-of-charge levels of 100%, 90%, 80%, 70%, 60% and 50%. With the CA-12 in “Scan Mode,” scan the batteries and load the data to PC-Companion software. Send the records with battery ID to Cadex for matrix development. You can also send test batteries to a Cadex laboratory.